1. Field of the Invention
The present invention relates to a hydrophilic plant growth substrate, more in particular to a substrate based on a coherent matrix of mineral wool which is hydrophilic due to he use of a specific cured resin.
2. Background of the Invention
Plant growth substrates may have the form of plugs accommodated in a tray hole, of cubes having a foil around the standing side surfaces, or of plastic wrapped slabs.
The currently used plant growth substrates which are based on a coherent matrix of mineral wool use as a cured binder generally a phenol-formaldehyde resin. Due to the use of this type of binder, the matrix of mineral wool has to be provided with a so-called wetting agent in order to impart the substrate with hydrophilic properties. That is, the matrix can adsorb in a relatively short time period up to saturation amounts of water.
Although these types of known plant growth substrates are widely used, there is constant research to improve plant growth substrates, in particular the phytotoxicity of the chemicals used. This phytotoxicity may result for instance from the used wetting agent, or due to the binder.